Comprehensive clinical and molecular characterization with long-term outcomes in 40 patients with congenital hyperinsulinism.

Abstract

Purpose: Congenital hyperinsulinism (CHI) represents the most frequent cause of recurrent hypoglycemia in neonates and infants, stemming from defects in the regulatory pathways of insulin secretion from pancreatic beta cells. This study aims to assess the clinical and genetic characteristics of a CHI cohort and to discuss the complexities involved in managing this heterogeneous disorder.

Methods: Forty patients (23 girls) with CHI were included in the study. Data on the diagnosis and treatment of CHI were obtained from the medical records.

Results: The median age at diagnosis was 1.4 months (range 0.1-30 months). The mean gestational age was 37.8 ± 2.4 weeks, and the birth weight was 1.1 ± 2.0 SDS. The consanguinity ratio was 35.0%. Median glucose, insulin, and C-peptide concentrations at diagnosis were 34.0 mg/dl (IQR 25.2-41.7), 12.4µU/ml (IQR 4.4-27.1), and 1.5 ng/ml (IQR 0.7-3.8), respectively. Molecular genetic diagnosis could be established in 62.5% (n = 25). Pathogenic variants were predominantly identified in the KATP channel genes (17/25, 68%), with the ABCC8 being the most frequent (n = 15; biallelic: 8, monoallelic: 7). KCNJ11 variants were identified in two (5.0%), GLUD1 variants in three (7.5%), and HADH variants in five patients (12.5%). Pancreatectomy was performed in 10 patients, with a mean age at the time of surgery of 3.9 ± 3.2 months. The genetic etiology was identified in all patients who underwent pancreatectomy, all of whom had defects in the KATP channel. ABCC8 variants were detected in nine (biallelic: 5, monoallelic: 4), while a biallelic variant in the KCNJ11 was identified in one case.

Conclusion: A molecular genetic diagnosis was identified in approximately two-thirds of our cohort, underscoring the significance of genetic testing in the management of CHI. Ongoing advances in genetic technologies are anticipated to enhance our understanding of the etiopathogenesis of CHI and support the development of more personalized therapeutic strategies. Although the genotype-phenotype correlation remains only partially elucidated, specific genetic variants may provide predictive insights into treatment resistance, thereby informing more targeted treatment approaches.